Real-time field friction reduction meter and method of use

ABSTRACT

A method of servicing a subterranean formation comprising communicating a servicing fluid comprising a hydratable friction reducer and a base fluid to the subterranean formation via a route of fluid communication, determining an actual percent by which the friction reducer reduces a pipe friction pressure, comparing the actual percent by which the friction reducer reduces the pipe friction pressure to an ideal percent by which the friction reducer should reduce pipe friction pressure to determine an effectiveness of the friction reducer, and determining if the effectiveness of the friction reducer is within an acceptable range. A method of servicing a subterranean formation comprising communicating a servicing fluid comprising a hydratable friction reducer and a base fluid to the subterranean formation via a route of fluid communication, measuring a wellhead pressure, determining a pipe friction pressure independent from the wellhead pressure, calculating a formation response pressure, and monitoring the formation response pressure.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO A MICROFICHE APPENDIX

Not applicable.

BACKGROUND

Hydrocarbon-producing wells often are serviced by a variety ofoperations involving introducing a servicing fluid into a portion of asubterranean formation penetrated by a wellbore. Examples of suchservicing operations include a fracturing operation, a hydrajettingoperation, an acidizing operation, or the like. In providing such aservicing fluid to the subterranean formation, it is often desirable toemploy a friction reducer to lessen the friction between the servicingfluid and the conduit through which the servicing fluid is communicatedto the formation.

Servicing fluids and the components comprising those servicing fluidsare diverse. As such, a given friction reducer may not be compatiblewith a given servicing fluid and, therefore, may be ineffective toreduce the friction between the servicing fluid and the conduit throughwhich the servicing fluid is communicated to the subterranean formation.Further, because the constituents and the relative amounts of thoseconstituents of a servicing fluid may be changed or varied over thecourse of a servicing operation, the effectiveness of a given frictionreducer may vary over the course of a servicing operation. As theeffectiveness of the friction reducer changes, the friction between theservicing fluid and the conduit through which the servicing fluid isflowing will also likely change. As such, because the friction betweenthe flowing servicing fluid and the conduit through which the servicingfluid flows changes, the pressure due to friction between the flowingservicing fluid and the innermost surface of the conduit, referred toherein as “pipe friction pressure,” may vary.

During a servicing operation, various factors contribute to the totalpressure experienced within the conduit through which the servicingfluid is communicated; the pipe friction pressure is one such component.Therefore, changes in the pipe friction pressure may yield a change inthe total pressure. Conventionally, there has been no means by which toassess whether a change in the total pressure is due to a change in theeffectiveness of the friction reducer employed (resulting in a change inthe pipe friction pressure) or to some other component of the totalpressure. In many situations, it is desirable to know whether changes inthe total pressure are the result of a change in the effectiveness ofthe friction reducer or some other factor. As such, there exists a needfor methods, systems, and apparatuses for determining the effectivenessof a friction reducer in subterranean formation servicing operations.

SUMMARY

Disclosed herein is a method of servicing a subterranean formationcomprising communicating a servicing fluid comprising a hydratablefriction reducer and a base fluid to the subterranean formation via aroute of fluid communication, determining an actual percent by which thefriction reducer reduces a pipe friction pressure, comparing the actualpercent by which the friction reducer reduces the pipe friction pressureto an ideal percent by which the friction reducer should reduce pipefriction pressure to determine an effectiveness of the friction reducer,and determining if the effectiveness of the friction reducer is withinan acceptable range.

Further disclosed herein is a method of servicing a subterraneanformation comprising communicating a servicing fluid comprising ahydratable friction reducer and a base fluid to the subterraneanformation via a route of fluid communication, measuring a wellheadpressure, determining a pipe friction pressure independent from thewellhead pressure, calculating a formation response pressure, andmonitoring the formation response pressure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial cutaway view of the operating environment of theinvention depicting a wellbore penetrating a subterranean formation.

FIG. 2 is a partial cutaway view of an embodiment of friction reducereffectiveness meter.

FIG. 3 is a schematic overview of a method of servicing a subterraneanformation.

FIG. 4 is a graph depicting the percent friction reduction over time forvarious servicing fluids.

DETAILED DESCRIPTION

Unless otherwise specified, use of the terms “connect,” “engage,”“couple,” “attach,” or any other like term describing an interactionbetween elements is not meant to limit the interaction to directinteraction between the elements and may also include indirectinteraction between the elements described.

Unless otherwise specified, use of the terms “up,” “upper,” “upward,”“uphole,” “upstream,” or other like terms shall be construed asgenerally from the formation toward the surface or toward the surface ofa body of water; likewise, use of “down,” “lower,” “downward,”“downhole,” “downstream,” or other like terms shall be construed asgenerally into the formation away from the surface or away from thesurface of a body of water, regardless of the wellbore orientation. Useof any one or more of the foregoing terms shall not be construed asdenoting positions along a perfectly vertical axis.

Unless otherwise specified, use of the term “subterranean formation”shall be construed as encompassing both areas below exposed earth andareas below earth covered by water such as ocean or fresh water.

Referring to FIG. 1, an embodiment of an operating environment for aFriction Reducer Effectiveness (FRE) meter and a method of using thesame is illustrated. It is noted that although some of the figures mayexemplify horizontal or vertical wellbores, the principles of thedevices, systems, and methods disclosed may be similarly applicable tohorizontal wellbore configurations, conventional vertical wellboreconfigurations, and combinations thereof. Therefore, the horizontal orvertical nature of any figure is not to be construed as limiting thewellbore to any particular configuration.

As depicted in FIG. 1, the operating environment generally comprises awellbore 114 that penetrates a subterranean formation 102 for thepurpose of recovering hydrocarbons, storing hydrocarbons, disposing ofcarbon dioxide, or the like. The wellbore 114 may be drilled into thesubterranean formation 102 using any suitable drilling technique. In anembodiment, a drilling or servicing rig comprises a derrick with a rigfloor through which a pipe string 150 (e.g., a drill string, segmentedtubing, coiled tubing, etc.) may be positioned within or partiallywithin the wellbore 114. A wellbore servicing apparatus 140 configuredfor one or more wellbore servicing operations may be integrated withinthe pipe string 150. Additional downhole tools may be included with orintegrated within the wellbore servicing apparatus and/or the pipestring 150 for example, one or more isolation devices, for example,packers such as swellable packers or mechanical packers.

The drilling or servicing rig may be conventional and may comprise amotor driven winch and other associated equipment for lowering the pipestring 150 into the wellbore 114. Alternatively, a mobile workover rig,a wellbore servicing unit (e.g., coiled tubing units), or the like maybe used to lower the pipe string 150 into the wellbore 114.

The wellbore 114 may extend substantially vertically away from theearth's surface over a vertical wellbore portion, or may deviate at anyangle from the earth's surface 104 over a deviated or horizontalwellbore portion. In alternative operating environments, portions orsubstantially all of the wellbore 114 may be vertical, deviated,horizontal, and/or curved. In some instances, a portion of the pipestring 150 may be secured into position within the wellbore 114 in aconventional manner using cement 116; alternatively, the pipe string 150may be may be partially cemented in wellbore 114; alternatively, thepipe string 150 may be uncemented in the wellbore 114. In an embodiment,the pipe string 150 may comprise two or more concentrically positionedstrings of pipe (e.g., a first pipe string may be positioned within asecond pipe string). It is noted that although some of the figures mayexemplify a given operating environment, the principles of the devices,systems, and methods disclosed may be similarly applicable in otheroperational environments, such as offshore and/or subsea wellboreapplications.

The devices, methods, and systems disclosed herein generally relate toan FRE meter. In an embodiment, the FRE meter may be employed toindependently determine one or more components of the total pressureduring a subterranean formation servicing operation. In an embodiment,independently determining one or more components of the servicing fluidmay allow adjustment of the servicing operation to achieve a desiredresult.

Referring again to FIG. 1, an embodiment of a route of fluidcommunication to the subterranean formation 102, illustrated by flowarrows 10, is shown in the context of a wellbore servicing equipmentspread or layout (e.g., a fracturing spread) assembled at a well site.In the embodiment of FIG. 1, the route of fluid communication 10 maygenerally comprise one or more storage vessels 230, one or more supplylines 220, a blending pump 210, a low-pressure-side conduit 200, one ormore pressurizing pumps 190, a high-pressure manifold 180, ahigh-pressure-side conduit 170, a wellhead 160, the pipe string 150,and, optionally, one or more pathways between the pipe string 150 andthe formation 102. Although FIG. 1 illustrates a general route of fluidcommunication to the subterranean formation 102, the FRE meter disclosedherein may be applicable to other suitable routes of fluidcommunication. For example, a route of fluid communication, like theroute of fluid communication illustrated in FIG. 1, may further comprisevarious other fluid conduits, such as, one or more conduits leading tothe manifold.

In an embodiment, the one or more storage vessels 230 may comprise anysuitable storage device, for example a tank, reservoir, hopper,container, or the like. The storage vessels 230 may be portable ormovable, alternatively, permanent or semi-permanent. The storage vessels230 may be configured to store a given material or substance as will benecessary for a given servicing operation. In a non-limiting example,the storage vessels may be individually configured for the storage of aliquid, a solid, a semi-solid, a suspension, a powder, a slurry, a gas,or combinations thereof. In an embodiment, one or more components of theservicing fluid may be stored in the one or more storage vessels. Forexample, a first storage vessel 230 may store a first servicing fluidcomponent (e.g., a base fluid, as will be discussed herein below), asecond storage vessel 230 may store a second servicing fluid component(e.g., a friction reducer, as will be discussed herein below), and athird, fourth, fifth, etcetera, storage vessel 230 may store one or moreadditional servicing fluid components.

In an embodiment, the one or more storage vessels 230 may be connectedto one or more supply lines. The supply lines 220 may comprise anysuitable conduit, nonlimiting examples of which include a pipe, a line,a tubing member, or the like. The supply lines may comprise flowboreextending therethrough. In an embodiment, the one or more supply lines220 may comprise a route of fluid communication between the storagevessels 230 and the blending pump 210. In an alternative embodiment, oneor more of the storage vessels 230 may be directly connected to theblending pump 210.

In an embodiment, the one or more supply lines 220 may be connected tothe blending pump 210. The blending pump 210 may comprise any suitableconfiguration. The blending pump 210 may be configured to blendservicing fluid components introduced therein and to discharge theresulting composition therefrom. The blending pump 210 may comprise aroute of fluid communication between the one or more supply lines 220and the low-pressure-side conduit 200.

In an embodiment, the blending pump 210 may be connected to alow-pressure-side conduit 200. The low-pressure-side conduit 210 maycomprise any suitable conduit, nonlimiting examples of which include apipe, a line, a tubing member, or the like. The low-pressure-sideconduit 200 may comprise a flowbore extending therethrough. Thelow-pressure-side conduit may comprise a route of fluid communicationbetween the blending pump 210 and the one or more pressurizing pumps190.

In an embodiment, the low-pressure-side conduit 200 may be connectedwith the one or more pressurizing pumps 190. The pressurizing pumps 190may be configured to increase the pressure of a fluid movingtherethrough. Although FIG. 1 illustrates three independent pressurizingpumps, any suitable number of pumps may be employed. The pressurizingpumps may comprise any suitable type or configuration of pump.Nonlimiting examples of a suitable pump include a centrifugal pump, agear pump, a screw pump, a roller pump, a scroll pump, a piston pump, aprogressive cavity pump, or combinations thereof. The one or morepressurizing pumps 190 may comprise a route of fluid communicationbetween the low-pressure-side conduit 200 and the manifold 180.

In an embodiment, the one or more pressurizing pumps 190 may beconnected with the manifold 180. The manifold 180 may suitably compriseone or more pipes, lines, valves, connections, the like, or combinationsthereof. In an embodiment, the manifold 180 may be configured to mergetwo or more fluid streams (e.g., from the one or more pressurizing pumps190) into a single fluid stream. The manifold 180 may comprise aflowbore comprising a route of fluid communication between thepressurizing pumps 190 and the high-pressure-side conduit 170.

In an embodiment, the manifold 180 may be connected with thehigh-pressure-side conduit 170. The high-pressure-side conduit 170 maycomprise any suitable conduit, nonlimiting examples of which include apipe, a line, a tubing member, or the like. The high-pressure-sideconduit 170 may comprise an axial flowbore extending therethrough. Thehigh-pressure-side conduit 170 may comprise a route of fluidcommunication between the manifold 180 and the wellhead 160.

In an embodiment, the high-pressure-side conduit 170 may be connectedwith the wellhead 160. The wellhead may suitably comprise one or morepipes, lines, valves, connections, the like, or combinations thereof.The wellhead 160 may comprise one or more flowbores for thecommunication of a fluid therethrough. The wellhead 160 may comprise aroute of fluid communication between the high-pressure-side conduit 170and the pipe string 150.

In an embodiment, the wellhead 160 may be connected to the pipe string150. The pipe string 150 may comprise a flowbore for the communicationof fluid therethrough. In various embodiments, the pipe string 150 maycomprise a casing string, a liner, a production tubing, coiled tubing, adrilling string, the like, or combinations thereof. The pipe string 150may extend from the earth's surface 104 downward within the wellbore 114to a predetermined or desirable depth.

In an embodiment where the route of fluid communication 10 comprises awellbore servicing apparatus 140, the wellbore servicing apparatus 140or some part thereof may be incorporated or integrated within the pipestring 150. The wellbore servicing apparatus 140 may be configured toperform a given servicing operation, for example, fracturing theformation 102, expanding or extending a fluid path through or into thesubterranean formation 102, producing hydrocarbons from the formation102, or other servicing operation. In an embodiment, the wellboreservicing apparatus 140 may comprise one or more ports, apertures,nozzles, jets, windows, or combinations thereof for the communication offluid from the flowbore of the pipe string 150 to the subterraneanformation 102. In an embodiment, the wellbore servicing apparatuscomprises a housing comprising a plurality of housing ports, a sleevebeing movable with respect to the housing, the sleeve comprising aplurality of sleeve ports, the plurality of housing ports beingselectively alignable with the plurality of sleeve ports to provide afluid flow path from the wellbore servicing apparatus to the wellbore,the subterranean formation, or combinations thereof. Such a wellboreservicing apparatus is described in greater detail in U.S. applicationSer. No. 12/274,193, which is incorporated in its entirety herein byreference.

Persons of ordinary skill in the art with the aid of this disclosurewill appreciate that the components of route of fluid communication 10described herein may be connected and/or coupled via any suitableconnection. Nonlimiting examples a suitable connections may includeflanges, collars, welds, or combinations thereof. One of more of thecomponents of route of fluid communication 10 may include variousconfigurations of pipe tees, elbows, the like, or combinations thereof.

In an embodiment the FRE meter generally comprises a route of fluidcommunication of a servicing fluid, a side-stream from the route offluid communication, a flow meter disposed in the side-stream, two ormore pressure gauges, optionally, a flow regulator, and, optionally, aside-stream valve. The side-stream may be configured such that a portionof the servicing fluid flows may be diverted from the route of fluidcommunication through the side-stream.

Referring to FIG. 2, an embodiment of an FRE meter 300 is illustrated.In the embodiment of FIG. 2, the FRE meter comprises a side-stream 310,a first pressure gauge 320 a, a second pressure gauge 320 b, a flow-ratemeter 330, one or more optional side-stream valves 350, and an optionalflow regulator 340.

In an embodiment, the FRE meter 300 may be connected to one or moresuitable components of a route of fluid communication such as route offluid communication 10. In the embodiment of FIG. 2, the FRE meter 300is connected to and in fluid communication with the low-pressure-sideconduit 200. In alternative embodiments, one of skill in the art viewingthe instant disclosure will recognize that the FRE meter 300 might beconnected to the storage vessels 230, to the supply lines 220, theblending pump 210, the low-pressure-side conduit 200, the one or morepressurizing pumps 190, the manifold 180, the high-pressure-side conduit170, the wellhead 160, the pipe sting 150, or combinations thereof.

In an embodiment, the side-stream 310 comprises any suitable conduitthrough which at least a portion of the servicing fluid may be routed.Nonlimiting examples of such a conduit include a pipe, tube, the like,or combinations thereof. The side-stream 310 may comprise a flowboreextending therethrough and may be in fluid communication with the routeof fluid communication 10. In the embodiment of FIGS. 1 and 2, theside-stream 310 is connected to the low-pressure-side conduit 200 and isin fluid communication therewith such that a portion of the fluidflowing via route of fluid communication 10 may be selectively divertedthrough the side-stream 310.

The side-stream 310 may be of any suitable length and any suitablediameter. In an embodiment, the side-stream 310 comprises a conduit of asuitable, known diameter. In an embodiment, the diameter may be withinthe range of from about 0.25 inches to about 12 inches, alternatively,from about 0.5 inches to about 4 inches, alternatively, about 0.5inches. In an embodiment, the length of the side-stream 310 may bewithin the range of from about 1 foot to about 25 feet, alternatively,from about 1.5 feet to about 20 feet, alternatively, from about 2 feetto about 10 feet. The side-stream 310 may be characterized as straight,curved, looped, or combinations thereof and may comprise one or moreelbows, bends, joints, the like, or combinations thereof.

In an embodiment, the side-stream 310 conduit comprises a suitable innersurface. In an embodiment, the inner surface of the side-stream 310 maycomprise a suitable roughness, as will be appreciated by one of skill inthe art. For example, in an embodiment the relative roughness withrespect to the pipe diameter may be in the range of from about 0 toabout 0.05, alternatively, from about 0 to about 0.001.

In the embodiment of FIG. 2, the FRE meter 300 comprises a flow-ratemeter 330. In an embodiment, the flow-rate meter 330 is configured todetermine the rate at which a fluid is moving through the flowbore ofthe side-stream 310. The flow-rate meter 330 may comprise any type orconfiguration of device or apparatus suitable for measuring ordetermining a rate fluid of flow. Nonlimiting examples of a suitabletypes or configurations of a flow-rate meters include Coriolis mass flowmeters, differential pressure flow meters, electromagnetic flow meters,positive displacement flow meters, ultrasonic flow meters, turbine orpaddlewheel flow meters, variable area flowmeters, the like, orcombinations thereof.

In the embodiment of FIG. 2, the FRE meter 300 comprises a firstpressure gauge 320 a and a second pressure gauge 320 b. In anembodiment, the first pressure gauge 320 a, the second pressure gauge320 b, or both is configured to measure the pressure of the fluid at apoint within the side-stream 310. The first and second pressure gauges,320 a and 320 b, may comprise any suitable type or configuration ofpressure gauge for determining or monitoring the pressure of fluid.Non-limiting examples of a suitable pressure gauge include a hydrostaticgauge, a piston-type gauge, a liquid column gauge, a mechanical gauge, adiaphragm gauge, a piezoresistive strain gauge, a capacitive gauge, amagnetic gauge, a piezoelectric gauge, an optical fiber gauge, apotentiometric gauge, a resonant gauge, or combinations thereof. Thefirst pressure gauge 320 a, the second pressure gauge 320 b, or both maycomprise a suitable output, for example, a display, an electric signal,a dial, etcetera.

In an embodiment, the first pressure gauge 320 a and the second pressuregauge 320 b may be separated by a known distance. In the embodiment ofFIG. 2, the first pressure gauge 320 a and the second pressure gauge 320b are illustrated as being separated by distance d. In an embodiment,distance d may be within the range of from about 1 foot to about 25feet, alternatively, from about 1.5 feet to about 20 feet,alternatively, from about 2 feet to about 10 feet.

In an embodiment where the FRE meter 300 comprises one or moreside-stream valves 350, the side-stream valve 350 may comprise anysuitable device or apparatus configured to selectively alter, adjust,allow, disallow, or combinations thereof, flow of a fluid therethrough.The side-stream valves 350 may be manually manipulatable, automaticallymanipulatable, or combinations thereof. Suitable valves are generallyknown to one of skill in the art.

In an embodiment where the FRE meter 300 comprises a flow regulator 340,the flow regulator 340 may comprise any suitable device or apparatusconfigured to impede, resist, or prohibit fluid flow therethrough in agiven direction, for example, a check-valve. In an embodiment, the flowregulator may additionally be configured to selectively alter, adjust,allow, disallow, or combinations thereof, flow of a fluid therethrough,for example, a valve. Suitable devices or apparatuses operable as theflow regulator 340 are generally known to one of skill in the art.

In an embodiment, the FRE meter 300 disclosed herein may be employed toindependently determine the pipe friction pressure, the formationresponse pressure, or other components of the wellhead pressure.

In an embodiment, during a wellbore servicing operation several pressurecomponents may contribute to the total pressure which may be measured atthe wellhead, referred to as the “wellhead pressure.” For example, thewellhead pressure may comprise a formation response pressure component,a pipe friction pressure component, a hydrostatic fluid pressurecomponent, and one or more additional pressure components such asperforation friction. As used herein, “formation response pressure”refers to the component of the wellhead pressure attributable to theresponse of the subterranean formation into which the servicing fluid isintroduced during a servicing operation. A near-wellbore pressurecomponent and a formation friction pressure component may contribute tothe formation response pressure. As used herein, “near-wellborepressure” generally refers to pressure due to flow restrictions from theperforations to the fracture such as, for example, tortuosity. As usedherein “formation friction pressure” generally refers to the pressuredue to friction between a servicing fluid and a fracture as theservicing fluid moves through the fracture. As used herein, “pipefriction pressure” refers to the pressure due to pipe friction and “pipefriction” refers to the friction between the servicing fluid and theinner surface of the pipe string as the servicing fluid flows throughthe pipe string. As used herein, hydrostatic fluid pressure generallyrefers to the pressure at a given point within a fluid generally due tothe weight of the fluid above it.

In an embodiment, determining the pipe friction pressure independentfrom one or more other components of the wellhead pressure may allow theefficiency of the friction reducer included within the servicing fluidflowing via the route of fluid communication 10 to be ascertained orcalculated. In an embodiment, knowledge of the efficiency of thefriction reducer may allow an operator to adjust the servicing fluid toachieve a desired level of friction reducer efficiency.

In another embodiment, determining the formation response pressureindependent from one or more other components of the wellhead pressuremay provide an operator with valuable information regarding downholeconditions during the performance of the servicing operation. In anembodiment, knowledge of downhole conditions during the servicingoperation may allow an operator to adjust the servicing operationparameters to achieve one or more desired results.

In an embodiment, the servicing fluid may comprise any suitableservicing fluid. Nonlimiting examples of suitable servicing fluidsinclude a fracturing fluid, a perforating fluid, an acidizing fluid, adebris removal fluid, the like, or combinations thereof. In anembodiment, the servicing fluid may generally comprise a base fluid, afriction reducer, and, optionally, one or more additional componentswhich may include but are not limited to proppants, scale inhibitors,biocides, surfactants, breakers, relative permeability modifiers, or thelike.

In an embodiment, the base fluid may comprise an aqueous base fluid,alternatively, a substantially aqueous base fluid. In an embodiment, asubstantially aqueous base fluid comprises less than about 50% of anonaqueous component, alternatively less than about 45%, 40%, 35%, 30%,25%, 20%, 15%, 10%, 5%, 4%, 3%, 2% or 1% of a nonaqueous component byweight of the base fluid. In an embodiment, the base fluid may furthercomprise an inorganic monovalent salt, multivalent salt, or combinationsthereof. Nonlimiting examples of salts suitable for use in such a basefluid include water soluble chloride, bromide and carbonate, hydroxideand formate salts of alkali and alkaline earth metals, zinc bromide, andcombinations thereof. The salt or salts in the base fluid may be presentin an amount ranging from greater than about 0% by weight of the basefluid to a saturated salt solution. The water may be fresh water or saltwater. Examples of the base fluid include for are not limited to waterproduced from the subterranean formation, flowback water, watertransported to the site of the servicing operation, or both.

In an embodiment, the base fluid may comprise a nonaqueous base fluid.In an embodiment, a nonaqueous base fluid may comprise an oleaginousfluid. Nonlimiting examples of such an oleaginous olefins, kerosene,diesel oil, fuel oil, synthetic oils, linear or branched paraffins,olefins, esters, acetals, mixtures comprising crude oil, derivativesthereof, or combinations thereof.

In an embodiment, the base fluid may comprise an emulsion of an aqueousfluid and a nonaqueous fluid. Nonlimiting examples of an emulsioninclude an invert emulsion (a water-in-oil emulsion), an oil-in-wateremulsion, a reversible emulsion, or combinations thereof.

In an embodiment, the friction reducer may comprise any suitablefriction reducer. In an embodiment the friction reducer comprises ahydratable friction reducer. The hydratable friction reducer may beeffective to reduce friction between a servicing fluid comprising thefriction reducer and a conduit through which the servicing fluid iscommunicated. In an embodiment, the hydratable friction reducercomprises a polymer. Nonlimiting examples of a suitable polymer includea polyacrylamide, polyacrylate, a copolymer of polyacrylamide andpolyacrylate, a copolymer of polyacrylamide and2-acrylamido-2-methylpropane sulfonic acid (AMPS), polyethylene oxide,polypropylene oxide, a copolymer of polyethylene and polypropyleneoxide, polysaccharides, and combinations thereof. Other suitablefriction reducers will be known to those of skill in the art. Examplesof suitable friction reducers that are commercially available are FR-46,FR-56, FR-58, FR-66, FDP-S944-09, SGA-2, SGA-5, and SGA-18 fromHalliburton Energy Services, Inc.

In an embodiment, the one or additional components comprise any suitableservicing fluid components. Suitable servicing fluid components will beknown to those of skill in the art with the aid of this disclosure.Nonlimiting examples of such components include a proppant, an acid, anabrasive, a scale inhibitor, a rheology modifying agent, a resin, aviscosifying agent, a suspending agent, a breaker, a dispersing agent, asalt, an accelerant, a surfactant, a relative permeability modifier, aretardant, a defoamer, a settling prevention agent, a weightingmaterial, a vitrified shale, a formation conditioning agent, apH-adjusting agent, or combinations thereof. These additional componentsmay be included singularly or in combination.

In an embodiment, the base fluid, the friction reducer, and anyadditional component are blended together in any suitable order to formthe wellbore servicing fluid. In an embodiment, the attributes of one ormore of the components of the servicing fluid may vary from oneservicing operation to another. Further, the components of a servicingfluid or the relative amounts thereof may vary throughout the course ofa given servicing operation. Not intending to be bound by theory, thefriction reducer employed in a servicing fluid may vary in compatibilitywith the other servicing fluid components between servicing operationsor throughout a servicing operation, thereby causing the frictionreducer to vary as to its effectiveness. For example, the base fluid maycomprise water produced from the subterranean formation; because theattributes and/or relative amount of the produced water may vary overthe course of the servicing operation, the friction reducer may vary incompatibility with the base fluid and, as such, the effectiveness of thefriction reducer may vary. Not intending to be bound by theory, poordispersion, inversion, hydration, or combinations thereof of a frictionreducer may cause a friction reducer to exhibit less than a desiredlevel of effectiveness.

In an embodiment, it may be desirable for a friction reducer to be about100, alternatively, 95, 90, 85, 80, 75, or 70% effective. In anembodiment, where a friction reducer exhibits less than the desiredlevel of effectiveness, it may be desirable to adjust the servicingfluid, the route of fluid communication of the servicing fluid; orcombinations thereof to improve dispersion, inversion, hydration, orcombinations thereof and thereby increase friction reducereffectiveness.

Disclosed herein is an embodiment of a method of servicing asubterranean formation. In various embodiments, the servicing operationmay comprise a fracturing operating, a perforating and/or hydrajettingoperation, an acidizing operation, or combinations thereof. In theembodiment of FIG. 3, the servicing method 50 generally comprises thesteps of determining an ideal percent friction reduction for a givenfriction reducer 500, communicating a subterranean formation servicingfluid to the subterranean formation 510, and determining an actualpercent friction reduction 520. In an embodiment, the subterraneanformation servicing method optionally comprises calculating a percenteffectiveness of the friction reducer 530. In an embodiment, a servicingmethod optionally comprises adjusting at least one parameter of theservicing operation in response to the effectiveness of the frictionreducer 540.

In an embodiment, determining the ideal percent friction reduction 500,% FR_(Ideal), may comprise any suitable method. As used herein, the term“ideal percent friction reduction” refers to the ideal percentage bywhich the pipe friction is reduced by a friction reducer. The %FR_(Ideal) may be determined analytically, experimentally, orcombinations thereof.

In an embodiment, determining the % FR_(Ideal) 500 may comprise anexperimental determination. For a fluid flowing from a first point,Point A, to a second point, Point B, in a pipe, assuming that thediameter of the pipe remains constant, that the elevation of the pipebetween Point A and Point B is unchanged, and that the velocity of thefluid is constant along the pipe, the pressure at Points A and B may begenerally described in that the pressure at Point B, P_(B), is equal tothe pressure at Point A, P_(A), minus the pipe friction pressure,P_(Pipe). Therefore, assuming the foregoing, the pipe friction pressurewill be equal to the difference in the pressure at Point A and thepressure at Point B as shown in equation (I):

P _(Pipe) =P _(A) −P _(B)  Equation (I).

In an embodiment, determining the % FR_(Ideal) 500 may generallycomprise determining the pipe friction pressure for a fluid (e.g., freshwater) that does not comprise a friction reducer, P_(Initial), anddetermining the pipe friction pressure for fresh water comprising afriction reducer at its ideal effectiveness, P_(Ideal). In anembodiment, an experimental determination of the % FR_(Ideal) may alsogenerally comprise comparing the P_(Initial) with the P_(Ideal).

In an embodiment, determining the P_(Initial) comprises observing thedifference in P_(A) and P_(B) for fresh water from which a frictionreducer is absent while flowing through a conduit (e.g., a pipe, a testloop, a pressure loop, or the like). In an embodiment, determining theP_(Ideal) comprises observing the difference in P_(A) and P_(B) for thesame fresh water or a substantially similar fresh water with a frictionreducer while flowing through the same or a similar conduit.

In an alternative embodiment, determining the P_(Initial) comprisescalculating the change in pressure for a fluid (e.g., fresh water) fromwhich a friction reducer is absent at about ambient conditions (e.g.,about 25° C. and about 1 atm.) over a given portion of a flow conduit oflength L according to equation (II-A):

$\begin{matrix}{P_{Initial} = \frac{\rho \; V^{2}{Lf}}{2g_{c}D}} & {{Equation}\mspace{14mu} ( {{II}\text{-}A} )}\end{matrix}$

where ρ is the density of the fluid at about 25° C. and about 1 atm., Vis the velocity of the fluid, g_(c) is the gravitational constant, D isthe diameter of the flow conduit, and where f is the friction factor.The friction factor, f, may be calculated according to equation (III)for a fully turbulent fluid flow:

$\begin{matrix}{f = \{ {{- 2}\; {\log \lbrack {\frac{ɛ/D}{3.7} - {\frac{5.02}{Re}{\log ( {\frac{ɛ/D}{3.7} + \frac{14.5}{Re}} )}}} \rbrack}} \}^{- 2}} & {{Equation}\mspace{14mu} ({III})}\end{matrix}$

where ε is the pipe roughness, D is the diameter of the flow conduit,and Re is the Reynolds number as calculated for the fluid at about 25°C. and about 1 atm. (Shacham, M., Isr. Chem. Eng., 8, 7E (1976)).

As will be appreciated by one of skill in the art, one or more of thetime that the friction reducer is in contact with an aqueous fluid,temperature of the fluid, the solute (e.g., a salt) concentration of thefluid, the combinations of solutes of the fluid, the soluble andinsoluble organic materials of the fluid, the particulates of the fluid,the pressure of the fluid, or combinations thereof may vary theeffectiveness of the friction reducer utilized in such a fluid. In anembodiment, the fluid for which the pipe friction will be determinedcomprises freshwater. Not intending to be bound by theory, utilizingfreshwater to determine the pipe friction pressure may minimize theopportunity for incompatibility of the friction reducer; as such, thefriction reducer may be fully or substantially hydrated (and thereby,not intending to be bound by theory, maximally effective). In anembodiment, the friction reducer may be contacted with the fluid for 20seconds under appreciable flow or shear to ensure the friction reducermay be fully or substantially hydrated (and thereby, not intending to bebound by theory, maximally effective). In an embodiment, the maximumeffectiveness of a given hydratable friction reducer may be determinedwhere, for example, the friction reducer has been in contact with afluid for a given amount of time, the fluid is at a given temperature,the fluid is at a given solute (e.g., a salt) concentration, the fluidis at a given pressure, or combinations thereof.

In an embodiment, the presence of the friction reducer in the fluid mayreduce the amount of pipe friction. Therefore, the P_(Ideal) may be lessthan the P_(Initial). By comparing the P_(Ideal) and the P_(Initial),the percent by which the pipe friction is reduced, the % FR_(Ideal), maybe calculated according to equation (IV):

$\begin{matrix}{{\% \mspace{14mu} {FR}_{Ideal}} = {( {1 - \frac{P_{Ideal}}{P_{Initial}}} ) \times 100{\%.}}} & {{Equation}\mspace{14mu} ({IV})}\end{matrix}$

In an alternative embodiment, determining the % FR_(Ideal) 500 maycomprise an analytical determination. Such an analytical determinationof the % FR_(Ideal) may generally comprise calculating, deriving, orextrapolating % FR_(Ideal), P_(Ideal), P_(Initial), or combinationsthereof according to a suitable mathematical relationship.

In an embodiment, % FR_(Ideal) may be determined prior to the servicingoperation, at a site removed from the servicing operation, or both. Forexample, % FR_(Ideal) may be determined in a laboratory setting prior toa given servicing operation. In an embodiment, where a % FR_(Ideal) hasbeen determined for a given friction reducer, the previously determined% FR_(Ideal) may be employed. For example, a % FR_(Ideal) utilized in aprior or separate servicing operation may be employed as the %FR_(Ideal) for another servicing operation. It is specificallycontemplated that the % FR_(Ideal) associated with a friction reducermay be known or may be derived from other known data and, as such, neednot be determined for each and every servicing operation.

In an embodiment, the servicing method 50 comprises communicating aservicing fluid comprising the friction reducer the subterraneanformation 510. In an embodiment, the servicing fluid may be communicatedto the subterranean formation 102 via a suitable route of fluidcommunication, for example, referring to FIG. 1, route of fluidcommunication 10.

In an embodiment, the components of the servicing fluid may be providedfrom the one or more storage vessels 230 to the blending pump 210 viathe one or more supply lines 220. Alternatively, one or more of thecomponents may be introduced directly into the blending pump 210. Theservicing fluid components may be introduced at any suitable rate, inany suitable order, in any suitable ratio, as will be appreciated by oneof skill in the art. When mixed, the servicing fluid may be routed fromthe blending pump 210 to the one or more pressurizing pumps 190 via thelow-pressure-side conduit 200. A portion of the servicing fluid may berouted through each of the one or more pressurizing pumps 190, therebyincreasing the pressure of the servicing fluid moving within the routeof fluid communication 10. As will be appreciated by one of skill in theart, the servicing fluid may be pressurized to a suitable pressure,dependent upon the servicing operation being performed. The pressurizedservicing fluid may be routed from the one or more pressurizing pumps190 through the manifold 180, high-pressure-side conduit, wellhead 160,pipe string 150, and wellbore servicing apparatus 140 to thesubterranean formation 102. A portion of the servicing fluid may flowinto and/or through the subterranean formation 102. Additionally, aportion of the servicing fluid may be circulated through the wellbore114.

In an embodiment, the servicing method 50 may comprise determining theactual percent friction reduction, % FR_(Actual) 520. In an embodiment,% FR_(Actual) may be determined by any suitable method. As used herein,the term “actual percent friction reduction” refers to the actualpercentage by which the pipe friction of a servicing fluid is reduced bya given friction reducer.

In an embodiment, determining the % FR_(Actual) 520 may comprisediverting at least a portion of the servicing fluid through theside-stream 310, measuring the velocity of the diverted servicing fluid,measuring a change in pressure of the diverted servicing fluid over agiven distance, or combinations thereof.

In an embodiment, at least a portion of the servicing fluid flowing viathe route of fluid communication may be diverted into the side-stream310 of the FRE meter 300. In an embodiment, the portion of the servicingfluid that is diverted may be in the range of from about less than 1% toabout 99% of the total volume of servicing fluid, alternatively, fromabout 1% to about 20% of the total volume of servicing fluid,alternatively, from about 5% to about 15% of the total volume ofservicing fluid, alternatively, about 10% of the total volume ofservicing fluid. In an embodiment, the percentage of the total volume ofthe servicing fluid diverted into the side-stream 310 may be adjusted byopening or closing the side-stream valves 350.

In an embodiment, the average fluid velocity of the portion of theservicing fluid diverted into the side-stream 310 may be determined fromthe flow-rate meter 330. In an embodiment, the average fluid velocity ofthe fluid flowing through the side-stream may be any suitable velocity.In an embodiment, the average fluid velocity of the fluid flowingthrough the side-stream may be in the range of from about 1 to about 200feet per second (fps), alternatively, about 10 to about 100 fps,alternatively, about 20 to about 60 fps. In an embodiment, the averagefluid velocity of the fluid flowing through the side-stream 310 may beadjusted, for example, as by manipulation of one or more of theside-stream valves 350. In an embodiment, adjustment of one or more ofthe side-stream valves 350 may be manual, automatic, or combinationsthereof. For example, an operator viewing the average fluid velocity ofthe fluid within the side-stream 310 may manually adjust the side-streamvalve to achieve a desirable average fluid velocity.

Alternatively, the side-stream valves 350 may be automatically adjustedin response to the velocity of the fluid in the side-stream 310 asmeasured by the flow-rate meter (e.g., via a suitable connection betweenthe flow-rate meter 330 and the side-stream valves 350). In anembodiment, the velocity of the fluid flowing via the side-stream may beemployed in comparing the ideal percent friction reduction for thefriction reducer, % FR_(Ideal), to the actual friction reduction forthat friction reducer, % FR_(Actual). For example, because % FR_(Ideal)may depend largely on fluid velocity and shear rate, it may beadvantageous, alternatively, necessary, to know the fluid velocity atwhich % FR_(Actual) occurs to ensure that % FR_(Actual) is compared tothe appropriate % FR_(Ideal), which is discussed in greater detailbelow.

In an embodiment, the flow of the servicing fluid through theside-stream 310 may be characterized as a turbulent flow. As will beappreciated by one of skill in the art, turbulent flow is a flow regimethat may be characterized by secondary flows appreciable in magnitudecompared to the primary flow direction, eddies, and apparent randomness.Conversely, non-turbulent flow may be referred to as laminar flow. TheReynolds number, a dimensionless number that relates the ratio ofinertial forces to viscous forces, often indicates whether a flow regimewill be characterized as turbulent or laminar for a given flow geometry.Generally Newtonian fluids flowing in pipes with circularcross-sections, flow regimes where the Reynolds number is greater thanabout 2000 may be characterized as turbulent flow while flow regimeswhere the Reynolds number is less than about 2000 may be characterizedas laminar flow.

In an embodiment, the change in the pressure of the portion of theservicing fluid flowing over distance d within the FRE meter 300 isdetermined using the first pressure gauge 320 a and the second pressuregauge 320 b. Not intending to be bound by theory, as discussed above,for a fluid flowing from a first point, Point A, to a second point,Point B, in a pipe, assuming that the diameter of the pipe remainsconstant, that the elevation of the pipe between Point A and Point B isunchanged, and that the velocity of the fluid is constant along thepipe, the pressure at Point A (e.g., as measured by the first pressuregauge 320 a) and the pressure at Point B (e.g., as measured by thesecond pressure gauge 320 b) may be generally described in that thepressure at Point B, P_(B), is equal to the pressure at Point A, P_(A),minus the pipe friction pressure, P_(Pipe). Therefore, assuming theforegoing, the pipe friction pressure may be calculated according toequation (I):

P _(Pipe) =P _(A) −P _(B)  Equation (I).

In an embodiment, determining % FR_(Actual) 520 may comprise determiningthe pipe friction pressure for the servicing fluid from which thefriction reducer is absent, P₀; determining the pipe friction pressurefor the servicing fluid comprising a friction reducer, P_(Actual); andcomparing the P₀ with the P_(Actual).

In an embodiment, determining the P₀ may comprise observing thedifference in P_(A) and P_(B) for a servicing fluid from which afriction reducer is absent. In an embodiment, determining the P_(Actual)may comprise observing the difference in P_(A) and P_(B) for a servicingfluid comprising a friction reducer. By comparing the P₀ and theP_(Actual), the % FR_(Actual) may be calculated according to equation(V):

$\begin{matrix}{{\% \mspace{14mu} {FR}_{Actual}} = {( {1 - \frac{P_{Actual}}{P_{0}}} ) \times 100{\%.}}} & {{Equation}\mspace{14mu} (V)}\end{matrix}$

In an alternative embodiment, the P₀ may be estimated, calculated, orotherwise determined based upon a prior known value, for example, basedupon the value of P_(Initial) used in determining % FR_(Ideal) asdescribed above.

In another embodiment, P₀ may be calculated (similar to the calculationof P_(Initial) given above) by equation (II-B):

$\begin{matrix}{P_{0} = \frac{\rho \; V^{2}{Lf}}{2g_{c}D}} & {{Equation}\mspace{14mu} ( {{II}\text{-}B} )}\end{matrix}$

where L is the length of the flow conduit, ρ is the density of the fluidat 25° C. and about 1 atm., V is the velocity of the fluid, g_(c) is thegravitational constant, D is the diameter of the flow conduit, and wheref is the fiction factor. The friction factor, f, may be calculatedaccording to equation (III) for a fully turbulent fluid flow:

$\begin{matrix}{f = \{ {{- 2}\; {\log \lbrack {\frac{ɛ/D}{3.7} - {\frac{5.02}{Re}{\log ( {\frac{ɛ/D}{3.7} + \frac{14.5}{Re}} )}}} \rbrack}} \}^{- 2}} & {{Equation}\mspace{14mu} ({III})}\end{matrix}$

where ε is the pipe roughness, D is the diameter of the flow conduit,and Re is the Reynolds number as calculated for the fluid at about 25°C. and about 1 atm. (Shacham, M., Isr. Chem. Eng., 8, 7E (1976)).

In an embodiment, the servicing method 50 comprises calculating theeffectiveness of the friction reducer 530. In an embodiment, calculatingthe effectiveness of the friction reducer 530 comprises comparing theideal percent friction reduction for the friction reducer, % FR_(Ideal),to the actual friction reduction for that friction reducer, %FR_(Actual). By comparing % FR_(Actual) and % FR_(Ideal), theeffectiveness, expressed as a percent, may be calculated according toequation (VI):

$\begin{matrix}{{Effectiveness} = {{\frac{\% \mspace{14mu} {FR}_{Actual}}{\% \mspace{14mu} {FR}_{Ideal}} \cdot 100}{\%.}}} & {{Equation}\mspace{14mu} ({VI})}\end{matrix}$

In an embodiment, the FRE meter 300 and the methods disclosed herein mayyield a measure of friction reduction and/or friction reducereffectiveness at a time from about 10 to about 60 seconds after thefriction reducer has been injected into the servicing fluid (e.g., theFRE meter measures the pipe friction pressure at a point downstream fromwhere the components of the servicing fluid are first mixed, as shown inFIG. 1). The FRE meter 300 and the methods disclosed herein may yield ameasure of friction reduction and/or friction reducer effectiveness thatis instantaneous and/or in real-time.

In an embodiment, the FRE Meter 300 allows for the determination of thepipe friction pressure independent from one or more other components ofthe wellhead pressure. In an embodiment where the pipe friction pressureis known, it may be possible to calculate or monitor changes in one ormore other components of the wellhead pressure. For example, it may bepossible to calculate the formation response pressure component, thehydrostatic fluid pressure component, or one or more additional pressurecomponents independent from the wellhead pressure.

In an embodiment, the servicing method 50 further comprises adjusting atleast one parameter of the servicing operation 540. In an embodiment,adjusting at least one parameter of a servicing operation 540 mayincrease the efficiency of a friction reducer, effect a change in theservicing operation, or combinations thereof.

As discussed above, a given friction reducer may vary as to itseffectiveness dependent upon the servicing fluid in which it is used,and/or other components present within the servicing fluid. As such, itmay be desirable to adjust one or more parameters of the servicingoperation to achieve a desirable friction reducer effectiveness. In anembodiment where the effectiveness of a friction reducer is less thandesired, an operator may adjust one or more parameters of the servicingoperation to increase the effectiveness of the friction reducer.

As discussed above, the formation response pressure may indicate thepresence or absence of a condition within a downhole portion of thewellbore and/or the subterranean formation. As such, it may be desirableto adjust one or more parameter of the servicing operation where theformation response pressure so-indicates.

In an embodiment adjusting one or more parameters of the servicingoperation may comprise altering, changing, adjusting the composition ofthe servicing fluid, for example, by altering, changing, adjusting thebase fluid of the servicing fluid, one or more components of theservicing fluid, the friction reducer used therein, or combinationsthereof in order to achieve a desired effectiveness. For example, theoperator might adjust or alter the servicing fluid by changing theamount or proportion of some component, adding a component, altering apH, changing the amount, type, or proportion of friction reducer used,using a different friction reducer, using a combination of frictionreducers, or combinations thereof.

In an embodiment, adjusting at least one parameter of the servicingoperation may comprise altering, changing, or adjusting the route offluid communication of the servicing fluid in response to theeffectiveness of the friction reducer. For example, the operator mightalter the amount of time for hydration of the friction reducer, alterthe amount of time prior to communicating the servicing fluid to thesubterranean formation, alter the amount of time the servicing fluid ismixed, alter the pressure at which the servicing fluid is communicatedto the subterranean formation, alter the volume of servicing fluidcommunicated to the subterranean formation, or combinations thereof.

In an embodiment, one or more of the steps of the servicing methoddisclosed herein may be implemented in software on one or more computersor other computerized components having a processor, user interface,microprocessor, memory, and other associated hardware and operatingsoftware. Software may be stored in tangible media and/or may beresident in memory on the computer Likewise, input and/or output fromthe software, for example ratios, percentages, comparisons, and resultsmay be stored in a tangible media, computer memory, hardcopy such apaper printout, or other storage device.

In an embodiment, data (e.g., pressures, pressure differentials, etc.)obtained from the performance of the foregoing methods may be input intoa computer automatically via a suitable interface; alternatively, datamay be input by a user or operator. Calculations and comparisons (e.g.,percent effectiveness, ideal percent friction reduction, actual percentfriction reduction) may be performed by a suitable computer orcomputerized component; alternatively, calculations and comparisons maybe performed by a user or operation. A suitable computer or computerizedcomponent may effect changes to the servicing operation (e.g., changesto the servicing fluid, the route of fluid communication, or both)responsive to a calculation, comparison, or both (e.g., a comparison ofthe actual effectiveness of a friction reducer with the desiredeffectiveness of the friction reducer) via a suitable interface (e.g.,electric, electronic, mechanical, or combinations thereof);alternatively, the results of a calculation or comparison may beprovided to a user or operator via a suitable display (e.g., aprint-out, a screen, etc) and the user or operator may decide whetherchanges to the servicing operation are desirable and, if so effect oneor more changes to the servicing operation via one or more suitablecontrol means (a dial, switch, level, etc).

In an embodiment, the devices, systems, and/or methods of the instantdisclosure may be employed to introduce a fracture into a subterraneanformation (e.g., a fracturing operation). Hydrocarbon-producing wellsoften may be stimulated by hydraulic fracturing operations. In anembodiment of a fracturing operation, a fracturing fluid, such as aparticle laden fluid, is pumped at relatively high-pressure into awellbore. The fracturing fluid may be introduced into a portion of asubterranean formation at a sufficient pressure and/or velocity and/orinitiate, create, extend, or enhance at least one fracture therein.Proppants, such as grains of sand, may be mixed with the fracturingfluid to keep the fractures open so that hydrocarbons may be producedfrom the subterranean formation and flow into the wellbore. Hydraulicfracturing may desirably create high-conductivity fluid communicationbetween the wellbore and the subterranean formation.

In an embodiment, the method of introducing a fracture into asubterranean formation comprises preparing a fracturing fluid. In suchan embodiment, the servicing fluid comprises a fracturing fluidcomprising a base fluid, a proppant, a hydratable friction reducer, and,optionally, additives.

In an embodiment, the base fluid may comprise water. The water may bepotable, non-potable, untreated, partially treated, treated water, orcombinations thereof. In an embodiment, the water may be produced waterthat has been extracted from the wellbore while producing hydrocarbonsform the wellbore. The produced water may comprise dissolved and/orentrained organic materials, salts, minerals, paraffins, aromatics,resins, asphaltenes, and/or other natural or synthetic constituents thatare displaced from a hydrocarbon formation during the production of thehydrocarbons. In an embodiment, the water may be flowback water that haspreviously been introduced into the wellbore during wellbore servicingoperation. The flowback water may comprise some hydrocarbons, gellingagents, friction reducers, surfactants and/or remnants of wellboreservicing fluids previously introduced into the wellbore during wellboreservicing operations. The water may further comprise local surface watercontained in natural and/or manmade water features (such as ditches,ponds, rivers, lakes, oceans, etc.). Still further, the water maycomprise water stored in local or remote containers. The water may bewater that originated from near the wellbore and/or may be water thathas been transported to an area near the wellbore from any distance. Insome embodiments, the water may comprise any combination of producedwater, flowback water, local surface water, and/or container storedwater.

In an embodiment, proppant, the base fluid, the hydratable frictionreducer, and, optionally, the additives are fed into the blending pump210 via supply lines 220. The blending pump 210 mixes solid and fluidcomponents to achieve a well-blended fracturing fluid. The mixingconditions of the blending pump 210, including time period, agitationmethod, pressure, and temperature, may be chosen by one of ordinaryskill in the art with the aid of this disclosure to produce ahomogeneous blend having a desirable composition, density, andviscosity. In alternative embodiments, however, sand or proppant, water,friction reducer, and/or additives may be premixed and/or stored in astorage tank.

In an embodiment, the method of introducing a fracture into asubterranean formation comprises determining the ideal percent frictionreduction, % FR_(Ideal), for a given friction reducer. As disclosedabove, the % FR_(Ideal) may be determined by experimental means. Forexample, it may be determined that a given friction reducer ideally mayreduce pipe friction by about up to 80% (% FR_(Ideal)=80%) at about15-25 seconds after injection of the friction reducer into the basefluid.

In an embodiment, the method of introducing a fracture into asubterranean formation comprises communicating the fracturing fluid to asubterranean formation via a suitable route of fluid communication, forexample, route of fluid communication 10 disclosed herein. In anembodiment, the pressurizing pumps 190 may pressurize the fracturingfluid to a pressure suitable for delivery into the wellhead 160. Forexample, the pressurizing pumps 190 may increase the pressure of thefracturing fluid to a pressure of up to about 20,000 psi or higher. Inan embodiment, the fracturing fluid may be combined to achieve a totalfluid flow rate that enters the wellhead 160 at a total flow of betweenabout 1 BPM to about 200 BPM, alternatively from between about 50 BPM toabout 150 BPM, alternatively about 100 BPM.

During the communication of the fracturing fluid, a portion of thefracturing fluid may be diverted from the route of fluid communicationthrough an FRE meter so as to determine the actual percent frictionreduction, % FR_(Actual). In an embodiment, to determine % FR_(Actual),the pipe friction pressure for the servicing fluid from which thefriction reducer is absent, P₀, may be calculated by equation (II-B):

$\begin{matrix}{P_{0} = \frac{\rho \; V^{2}{Lf}}{2g_{c}D}} & {{Equation}\mspace{14mu} ( {{II}\text{-}B} )}\end{matrix}$

where L is the length of the flow conduit, ρ is the density of the fluidat 25° C. and about 1 atm., V is the velocity of the fluid, g_(c) is thegravitational constant, D is the diameter of the flow conduit, and wheref is the fiction factor. The friction factor, f, may be calculatedaccording to equation (III) for a fully turbulent fluid flow:

$\begin{matrix}{f = \{ {{- 2}\; {\log \lbrack {\frac{ɛ/D}{3.7} - {\frac{5.02}{Re}{\log ( {\frac{ɛ/D}{3.7} + \frac{14.5}{Re}} )}}} \rbrack}} \}^{- 2}} & {{Equation}\mspace{14mu} ({III})}\end{matrix}$

where ε is the pipe roughness, D is the diameter of the flow conduit,and Re is the Reynolds number as calculated for the fluid at about 25°C. and about 1 atm. (Shacham, M., Isr. Chem. Eng., 8, 7E (1976)).P_(Actual) may be determined by measuring the pipe pressure of theservicing fluid having the friction reducer present as the servicingfluid flows via the FRE meter. Therefore, as disclosed above, comparingP₀ with P_(Actual) yields the actual percent by which the frictionreducer reduces pipe friction. For example, it may be determined that agiven friction reducer actually reduces pipe friction by 60% (%FR_(Actual)=60%) at about 15-25 seconds after injection into thefracturing fluid. As disclosed above, comparing the % FR_(ideal) withthe % FR_(Actual) yields the percent effectiveness. For example, afriction reducer that ideally reduces pipe friction by 80% and actuallyreduces pipe friction by 60% would be 75% effective.

In an embodiment where the percent effectiveness of the friction reduceris less than a desired percent effectiveness, an operator may choose toadjust the composition of the servicing fluid, the route of fluidcommunication or both. For example, if an operator desired 90%effectiveness, where a friction reducer performed at 75% effectiveness,the operator might choose to adjust the composition of the servicingfluid, the route of fluid communication, or combinations thereof. In anembodiment, adjusting the composition of the servicing fluid, the routeof fluid communication, or combinations thereof may increase theeffectiveness of the friction reducer by, not intending to be bound bytheory, increasing the hydration, inversion, dispersion, or combinationsthereof of the friction reducer.

In an embodiment, the operator may adjust the composition of theservicing fluid by altering the amount of friction reducer, altering thetype of friction reducer, adding second friction reducer, adding acomponent to the base fluid, subtracting a component from the basefluid, altering the composition of the base fluid, or combinationsthereof. In an embodiment, the operator may adjust the route of fluidcommunication by altering the amount of time for hydration of thefriction reducer, altering the amount of time prior to communicating theservicing fluid to the subterranean formation, altering the amount oftime the servicing fluid is mixed, altering the pressure at which theservicing fluid is communicated to the subterranean formation, alteringthe volume of servicing fluid communicated to the subterraneanformation, or combinations thereof.

EXAMPLES

The embodiments having been generally described, the following examplesare given as embodiments of the disclosure and to demonstrate thepractice and advantages thereof. It is to be understood that theexamples are presented herein as a means of illustration and are notintended to limit the specification or the claims.

In each of the following examples, an FRE meter, for example, similar toFRE meter 300 disclosed herein, was used, for example, as by the methodsdisclosed herein, to measure friction reduction and/or the effectivenessof a friction reducer. The results of these examples are shown in FIG.4.

Example 1

1 gpt (gallons per thousand gallons) of FR-56 was injected into Duncantap water flowing at a nominal rate of 28 gallons per minute through a0.56-inch, smooth pipe. Approximately 20 seconds after the frictionreducer was injected, the instantaneous friction reduction was measuredat about 72%, and the friction reduction effectiveness was 100%. In anembodiment, this may represent % FR_(Ideal).

Example 2

1 gpt of FR-56 was injected into Duncan tap water containing 16 wt %CaCl (calcium chloride) flowing at a nominal rate of 28 gallons perminute through a 0.56-inch, smooth pipe. Approximately 20 seconds afterthe friction reducer was injected, the instantaneous friction reductionwas measured at about 30%, and the friction reduction effectiveness was42%.

Example 3

1 gpt of FR-46 was injected into untreated Velma field water flowing ata nominal rate of 10 gallons per minute through a 0.56-inch, smoothpipe. Approximately 20 seconds after the friction reducer was injected,the instantaneous friction reduction was measured at about 48%, and thefriction reduction effectiveness was 67%.

At least one embodiment is disclosed and variations, combinations,and/or modifications of the embodiment(s) and/or features of theembodiment(s) made by a person having ordinary skill in the art arewithin the scope of the disclosure. Alternative embodiments that resultfrom combining, integrating, and/or omitting features of theembodiment(s) are also within the scope of the disclosure. Wherenumerical ranges or limitations are expressly stated, such expressranges or limitations should be understood to include iterative rangesor limitations of like magnitude falling within the expressly statedranges or limitations (e.g., from about 1 to about 10 includes, 2, 3, 4,etc.; greater than 0.10 includes 0.11, 0.12, 0.13, etc.). For example,whenever a numerical range with a lower limit, R_(l), and an upperlimit, R_(u), is disclosed, any number falling within the range isspecifically disclosed. In particular, the following numbers within therange are specifically disclosed: R=R_(l)+k*(R_(u)−R_(l)), wherein k isa variable ranging from 1 percent to 100 percent with a 1 percentincrement, i.e., k is 1 percent, 2 percent, 3 percent, 4 percent, 5percent, . . . 50 percent, 51 percent, 52 percent, . . . , 95 percent,96 percent, 97 percent, 98 percent, 99 percent, or 100 percent.Moreover, any numerical range defined by two R numbers as defined in theabove is also specifically disclosed. Use of the term “optionally” withrespect to any element of a claim means that the element is required, oralternatively, the element is not required, both alternatives beingwithin the scope of the claim. Use of broader terms such as comprises,includes, and having should be understood to provide support fornarrower terms such as consisting of, consisting essentially of, andcomprised substantially of. Accordingly, the scope of protection is notlimited by the description set out above but is defined by the claimsthat follow, that scope including all equivalents of the subject matterof the claims. Each and every claim is incorporated as furtherdisclosure into the specification and the claims are embodiment(s) ofthe present invention. The discussion of a reference in the disclosureis not an admission that it is prior art, especially any reference thathas a publication date after the priority date of this application. Thedisclosure of all patents, patent applications, and publications citedin the disclosure are hereby incorporated by reference, to the extentthat they provide exemplary, procedural or other details supplementaryto the disclosure.

1. A method of servicing a subterranean formation comprising:communicating a servicing fluid comprising a hydratable friction reducerand a base fluid to the subterranean formation via a route of fluidcommunication; determining an actual percent by which the frictionreducer reduces a pipe friction pressure; comparing the actual percentby which the friction reducer reduces the pipe friction pressure to anideal percent by which the friction reducer should reduce pipe frictionpressure to determine an effectiveness of the friction reducer; anddetermining if the effectiveness of the friction reducer is within anacceptable range.
 2. The method of claim 1, further comprisingdetermining the ideal percent by which the friction reducer shouldreduce pipe friction pressure.
 3. The method of claim 1, wherein theideal percent by which the friction reducer should reduce pipe frictioncomprises a previously determined value.
 4. The method of claim 1,wherein determining the actual percent by which the friction reducerreduces the pipe friction comprises: diverting at least a portion of theservicing fluid from the route of fluid communication through a frictionreducer meter; measuring a pressure at a first point within the frictionreducer meter and a pressure at a second point within the frictionreducer meter; and calculating the difference between the pressure atthe first point and the pressure at the second point.
 5. The method ofclaim 4, wherein the flow of the portion of the servicing fluid divertedthrough the friction reducer meter comprises a turbulent fluid flow. 6.The method of claim 1, wherein the determination of the effectiveness ofthe friction reducer is determined at the instant of measuring thepressure at the first point within the friction reducer meter and thepressure at the second point within the friction reducer.
 7. The methodof claim 1, further comprising adjusting the composition of theservicing fluid, the route of fluid communication, or both in responseto the effectiveness of the friction reducer where the effectiveness ofthe friction reducer is not within the desirable range.
 8. The method ofclaim 7, wherein adjusting the composition of the servicing fluidcomprises altering the amount of friction reducer, altering the type offriction reducer, adding second friction reducer, adding a component tothe base fluid, subtracting a component from the base fluid, alteringthe composition of the base fluid, or combinations thereof.
 9. Themethod of claim 7, wherein adjusting the route of fluid communicationcomprises altering the amount of time for hydration of the frictionreducer, altering the amount of time prior to communicating theservicing fluid to the subterranean formation, altering the amount oftime the servicing fluid is mixed, altering the pressure at which theservicing fluid is communicated to the subterranean formation, alteringthe volume of servicing fluid communicated to the subterraneanformation, or combinations thereof.
 10. The method of claim 1, whereinadjusting the servicing fluid increases the hydration of the frictionreducer.
 11. The method of claim 1, wherein adjusting the servicingfluid increases the effectiveness of the friction reducer.
 12. Themethod of claim 1, wherein the route of fluid communication comprisesone or more storage vessels, one or more supply lines, a blending pump,a low-pressure-side conduit, one or more pressurizing pumps, a manifold,a high-pressure-side conduit, a wellhead, the pipe string, one or morepathways between the pipe string and the subterranean formation, orcombinations thereof.
 13. The method of claim 1, wherein the base fluidcomprises an aqueous base fluid.
 14. The method of claim 1, wherein theaqueous base fluid comprises water produced from the subterraneanformation.
 15. The method of claim 1, wherein the servicing fluidcomprises a fracturing fluid.
 16. The method of claim 15, wherein thefracturing fluid comprises a proppant.
 17. The method of claim 1,wherein the servicing fluid comprises a perforating fluid, ahydrajetting fluid, or combinations thereof.
 18. The method of claim 1,wherein the friction reducer comprises a polyacrylamide, a copolymer ofpolyacrylamide and acrylic acid, a copolymer of polyacrylamide and2-acrylamido-2-methylpropane sulfonic acid (AMPS), or combinationsthereof.
 19. The method of claim 1, wherein the servicing fluid furthercomprises a proppant, an acid, an abrasive, a scale inhibitor, arheology modifying agent, a resin, a viscosifying agent, a suspendingagent, a dispersing agent, a salt, an accelerant, a surfactant, aretardant, a defoamer, a settling prevention agent, a weightingmaterial, a vitrified shale, a formation conditioning agent, apH-adjusting agent, or combinations thereof.
 20. A method of servicing asubterranean formation comprising: communicating a servicing fluidcomprising a hydratable friction reducer and a base fluid to thesubterranean formation via a route of fluid communication; measuring awellhead pressure; determining a pipe friction pressure independent fromthe wellhead pressure; calculating a formation response pressure; andmonitoring the formation response pressure.
 21. The method of claim 20,wherein determining the pipe friction pressure comprises: diverting atleast a portion of the servicing fluid from the route of fluidcommunication through a friction reducer meter; measuring a pressure ata first point within the friction reducer meter and a pressure at asecond point within the friction reducer meter; and calculating thedifference between the pressure at the first point and the pressure atthe second point.
 22. The method of claim 21, wherein the flow of theportion of the servicing fluid diverted through the friction reducermeter comprises a turbulent fluid flow.
 23. The method of claim 20,further comprising adjusting the composition of the servicing fluid,adjusting the route of fluid communication, or both in response to theformation response pressure.
 24. The method of claim 23, whereinadjusting the composition of the servicing fluid comprises altering theamount of friction reducer, altering the type of friction reducer,adding second friction reducer, adding a component to the base fluid,subtracting a component from the base fluid, altering the composition ofthe base fluid, altering the type of servicing fluid communicated, orcombinations thereof.
 25. The method of claim 23, wherein adjusting theroute of fluid communication comprises altering the amount of time priorfor hydration of the friction reducer, altering the amount of time priorto communicating the servicing fluid to the subterranean formation,altering the amount of time the servicing fluid is mixed, altering thepressure at which the servicing fluid is communicated to thesubterranean formation, altering the volume of servicing fluidcommunicated to the subterranean formation, or combinations thereof. 26.The method of claim 20, wherein adjusting the communication of theservicing fluid comprises altering the pressure at which fluid iscommunicated, altering the rate at which fluid is communicated, orcombinations thereof.
 27. The method of claim 20, wherein the servicingfluid comprises a fracturing fluid, a perforating fluid, a hydrajettingfluid, or combinations thereof.
 28. The method of claim 20, wherein theservicing fluid further comprises a proppant, an acid, an abrasive, ascale inhibitor, a rheology modifying agent, a resin, a viscosifyingagent, a suspending agent, a dispersing agent, a salt, an accelerant, asurfactant, a retardant, a defoamer, a settling prevention agent, aweighting material, a vitrified shale, a formation conditioning agent, apH-adjusting agent, or combinations thereof.
 29. The method of claim 20,wherein the route of fluid communication comprises one or more storagevessels, one or more supply lines, a blending pump, a low-pressure-sideconduit, one or more pressurizing pumps, a manifold, ahigh-pressure-side conduit, a wellhead, the pipe string, one or morepathways between the pipe string and the subterranean formation, orcombinations thereof.